Braking device for towed vehicles



My 24,1951 1 QWWAMS 2,529

BRAKING DEVICE FOR TOWED VEHICLES Filed June 28, 1949 2 Sheets-Sheet 1 IN VEN TOR. 0955 new W/L 14 MM:

July 2 3, 1951 c. WILLIAMS BRAKING DEVICE FOR TOWED VEHICLES Filed June 28, 1949 2 Sheets-Sheet 2 INVEN TOR. @955 7'EQ W/Li MMS Patented July 24, !951 UNl'lED STATES OFFICE.

' ,i'geeems. 1';

BRAKING DEVICE FORjTOWEDf VEHICLES I Chester Williams, Ypsilanti, Mien.

n plieati nzlune zls, 194- ,se ms-10 70:

This invention relates to and has particular reference to a braking device 'for an automobile being towed by another with a bumper to bumper hitch. Anobject of the invention is to generally improve towing devices and to provide a bumperto "bumper automobile towing device which is provided with means to automatically brake' and otherwise control the towed vehicle;

Another object of the invention is toprovide "animproved automatic braking mechanism for a towed automobile, which is readily applicable to-the well known Red Arrow towbar.

, Anotherobject of the invention is to provide a device of the character indicated in which-the braking characteristics of the towed vehicle can be adjusted to suit driver requirements or road conditions, by a simple adjustment of theispring tension on the brake arm. a

Another object of the invention is the provision of a device of the character indicated in which the braking action on the towed vehicle occurs only during the positive brakin action of the towing vehicle. This isaccomplished by-means of proper adjustment of the spring tension on the brake arm member and by the use of a cam at the lower end of the brake arm, which cam is provided with considerable friction which-prevents the-movement of the brake arm by minor shock loads such as experienced when crossing-a --railroad track 01' whentravelingover roaduimperfections. 1 i 5 Another object of the invention is the provision of a combined towing and automatic braking device which is constructed and arranged to obviate any tendency of the brake on the towed vehicle to stick. This result is accomplished by maintaining a proper spring load on the upper part of the brake arm of the device.

Another object of the invention is the provision of a towing and brakin mechanism which is constructed and arranged to provide positive sive spring loads carried on the braking members of the device. .1

' Another object of the invention-is to provide a separate brake assembly which is readilyfsubstituted for one of the elements'comprising a 'conventional bumper to bumper towbari automotive vehicles 7 Claims. (cuss-112 2 Another object of the invention is the provi sionof a towing and braking mechanism which overcomes any tendency of the towed-vehicle to surge, there being means for adjusting-a the strength of the surge resistance. Another object of the invention is the provision of a device of the character indicated which is provided with counter-acting spring tension means I. V,

Another" object of the invention is the provision of a device of the character indicated which enables the operator to back both the towed and the towing vehicle without putting on the brakes. Another object of the invention is to provide a towing and braking mechanism which is constructed and arranged so that the braking tension maybe'so finely adjusted that properbraking action may be efiected on the towed automobile even on icy roads.

Another object of the invention is the provision of a'towing and brakingmechanism ,which jerk on the to'wed vehicle which would overcome the spring tension ,on the braking mechanism and would cause the brakes on the towed car to be actuated.

The foregoing and other objects andadvantages' of theinvention. will become more apparent I as the description proceeds, reference being made from time to time to the accompanying drawings forming part .ofthe within disclosure, in which drawings: i

:Fig. 1 is'av bottom plan View of towed andtowing vehicles equipped with a device embodying the invention.

t. Fig. 2-is. a side elevationalview of the vehicles and device shown in Fig. 1.

Figs-3 is an enlargedbottom plan view of the device taken substantially on the line 33 of Fig. 4 is a longitudinal section taken substan- "I'he'towing vehicle 1 has a rear bumper 9 and the towed vehicle 8 has a front bumper l0, which -bumpers 9 and ID are preferably connectedby means of .a. Red Arrow towbar which is more -,fully described-in United States Letters Patent .-N0..2, Q,. 22;B4I i 3- The Red Arrow towbar consists generally of a yoke or draw beam II, a pull bar I2, and a pair of divergent arms I3 and I4, which said arms are pivoted as at I5 and I6 to a laminated submember I2A, comprising part of the pull bar I2. Equalizing spreader arms IT and I8, each consisting of two straps of metal in spaced relation to each other, are pivoted to the arms I3 and I4 as at I9and12il, and to a, pivotxcm'ember il which is slidable' in'a'slot 22 formed-'intlie-pull bar sub-member I2A. The arms I3 and I4 are preferably made of channel iron so that the spreader arms I1 and I8 may rideintheir-chan-v nels when the arms I3 and I4 are brought'together.

The yoke I I is secured at eitheriendtothe rear bumper 9 of the towing vehicle 'I' by means of clamps 23, and the divergent ends of theiarms: I32

and 14 are secured to the front bumper II] of the towed :vehicle, Ssbymeans; of clamps 24, Crossed steering; members 2 5 and "2 6 .areconnected .to ,the yoke;I I and to'the radius'rod .or steering;,arm.-2"I of the towed vehicle.

The foregoing elements comprise the principal parts of the devices disclosed in United States Letters Patent Nos.- 2,120,422=and 2;206,991,,and functionasthereindescribed, and form vnapart of the within invention except as they are-:combined with the elements hereinafter. described.

In the conventional JRed Arrow towbanthe pull bar '12 and :the 1 sub-member ql 2A are-rigidly fixed to one-anotherandare-not movable withrespect to each other, whereas "in theinstant embodiment the members-J2 and-1I2A-' are-longitudi nally: slidable with .-respect -to:; each other.

Referring now toe-Figs; 3 and 4, it lwilllbeiseen that the pull bar I2 isrprovi-ded:witha;bore:-28

which is adapted to accommodatea-zbolt orgpinilg (Fig; 1), whereby the: pull bar I2'-is-;pivotal-ly see cured to'the yoke I I. V A sl'oti3fl-is' also/formed; in the bar II! *and is adapted to: accommodate-a bolt 3!, which extends throughaeborextt formed in the sub-member- WA; A bushingfisgsurrounds the bolt 3| inthe slot anddsaslightlyr;longer than the thickness of the-bar; I2; soc that there can be'no tendency 'of the .pa-rtszto a'bindawhen drawn-down by the nut 34. Anzelongated masher (Fig. 4) which is wider than the slot 30, rests on the bushing '33 'and serves as aislidable base for The pull bar I2 is'also slottedasat 43 aiid tr l h= to accommodate the bolts I Eiand- I'6 whiclrpivot- 'ally secure the ends of 'thearms I3 and I4 .tozthe sub-member I2A. As previouslystated;theasubmember [2A consistso'r a plurality :of laminae-or plates which are preferably riveted togetherv-asca't 45.- The top andbottom plates462andi41 fare longer than the intermediate plates,*?andi'the plates 46 and 4-I'are formed with thesslots=s22 therein. It will be noted that-withrthis formr-ioi tially concealed thereby when the arms I3 and [4 are moved toward one another.

The member I2 is provided with still another slot 48 which is substantially in alignment with the slot 30. The slot 48 is adapted to accommodate the lower end of the braking arm 49 which is pivoted as at Eli in a clevis SI formed at the end of a bracket 52, which bracket 52 has out-- wardlyyextending ears15'3 through which, respectively, the bolts I5 and I6 extend. The bolts I5 and I6 are provided with over-size-in-length bushings in the slots 43 and 44 sothat there can benoi-bindingrbetween the member I2 and the cars 53 of "the bracket 52.

The loweraend of the braking arm 49 is provided with a cam surface 5 3 which is adapted to "ride against'the surface 55 comprising the end of thee-slot 48, so that upon the relative movement of the member I2 with respect to the member IZA,

:the braking arm ill may be moved. A tension springfili is secured atone endto thebra'kingarm ll; -and;at theother.end to the bracket 52; This spring tends to urge the lower e'nd of the braking arm. 49 into contacting relation with the pull A wire .cable 5'! extends through aisuitablebore initheupper endof the braking arm fill-and islsecured against displacement by-mean's ofraniadjustable member 58; The cable 51. extends throughr-arrubber covered wire wound loom 59 which. is secured at one end to the upper. end of the brackets)? and at the opposite end, as shown ineFigss land 2, tether steering postififlvof the towed-vehicle bymeans of astrap GI or other suitablevmeanss Theeendfil of the cable 5I is-rsecured-to :the brake. pedal I53 ofithetowedw vehicle so that "when :the +t0wed vehicle 8 tends :to. over run the towing vehicle I,- themember. I2A moves longitudinally with respect to the member I2 "causing the bracket 52, which carriesthe braking arm:49,' ;to' :movecorrespondingly, thereby, efiectingbrakingraction on the towed vehicle through thercable ?5:'I It :will: -bernotedthat the spring-4 I is much-'largerthan theispring =56 and. itsitension s, isxadj'ustableas previously described so ith-at by makinggtheproper adjustment onthersprin-g .-4-I azahigh ly, sensitive balance I-may be:; effected between the .members --I2- and I 2A=to efiect the-.re-

sultsapreviously;indicated.

Havingedescribed my, invention what Ieciaim and desire to secure by Letters Patent =is:;,

1; In; az'zdevice of the character'described; includinge'a pull bar arranged "for attachment to thecbumperpf a towing vehicle and apjair Y o-f=rdi- .ivergent arms s-arrangedfor attachment to. the

bumper of -atowed vehicle; the: combination of-va member underlying a portion ofsaid: pull. bar. :and slidable relative thereto-,- said .memben having pivoted theretothezends of said pair of: divergent 60- arms, "a bracket carried by said underlying mem- 1 ben-"a brakeiarm p'lvcted'tosaidbracketandchavin'g-ia pant-member arranged: to contact a pontion construction, the spreader arms .I 1 and I8 amen between the plates and-41 aiid are substanofsaidpullibar, 'awcable extending :frorrrsaid brake arm to: the ."brake "lever roff-the towed vehicle, and

-='spring means einterp'osed between said a'pu ll, -.bar

and said underlying member,:and.-spring;?means interposed between, said I brake arm-rand; the bracketecarried: by saidnnderlying ,mem-b era 2;: Therc'ombinati'on defined-in claim 1, in-which saiid zcab'le:slidably engagesa loom! which isse cured at one end to the said bracket-and-whichis "securedat the other end to a rigidt'elementonrsaid towedvehicle adjacent the said brakelever-e 3;:- Theicombination defined in. claim 1,.-;including meansiorcadjusting the tension entire-spring means interposed between the said pull bar and said underlying member.

4. In a device of the character described including a pull bar arranged for attachment to the rear bumper of a towing vehicle and a pair of divergentarms arranged for attachment to the front bumper of a towed vehicle, the combination of a member underlying one end of said pull bar and slidable relative thereto, said member having the converging ends of said diverging arms pivoted thereto, a bracket secured to said member by means extending through slots formed 5. The combination defined in claim 4,- including a pin secured to one end of said underlying member and extending through a slot formed in said pull bar, a bracket supported by said pin and slidable with reference to said pull bar, and an adjustable tension spring secured at one end to said bracket and secured at the other end to a member formed on said pull bar.

6. In a device of the character described, in combination, a pair of diverging arms pivoted at their converging ends to a member. comprising a plurality of metal plates, the upper and lower plates of said member having outwardly extended and slotted portions, spreader arms pivoted to said diverging arms and to a member slidable in the slots of said plate extensions, a fiat pull bar having longitudinal slots adapted to accommodate pins carried by said first named member and arranged for longitudinal movement relative thereto, brackets carried by said pins, one of said brackets being arranged to pivotally support a braking arm and fixedly support one end of a flexible loom, a braking arm pivoted to said last named bracket, there being a cable secured to said braking arm and slidable in said loom, the other said bracket being adapted to adjustably support a tension spring, and a tension spring secured at one end to said last named bracket and secured at the other end to a member formed on said pull bar. v

7. The combination defined in claim 6, including a tension spring secured at one end to said braking arm and secured at the other end to said first named bracket.

CHESTER WILLIAMS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number 

